Fig. 1.

Validation of the miR-1270 response element (MRE-1270) in the BSL region of IFN-α1 mRNA. a The schematic shows the predicted binding sites for miR-1270 (nt 333–308), miR-1287 (nt 324–303), and miR-483 (nt 226–205) (all in black bold lines) and their relation to the BSL region (IFNA1 nt 322–352; red bold line) in the conserved secondary structure of IFN-α1 mRNA. Figure reproduced with modification from Kimura et al. [11] with permission. b A series of pEF-Luc (luciferase) reporters harboring SL2, SL2/∆BSL or BSL of IFN-α1 mRNA were transfected into the recombinant pLKO-miR-1270 lentivirus-transduced Namalwa cells. Luciferase assays were performed 48 h after transfection as described previously [51]. The luciferase activities were normalized to the enzymatic activity determined in parental pEF-Luc reporter-transfected cells (Cont) and are presented as the “relative luciferase activity”, which indicates percent reporter activity relative to that of Cont as 100 %. Values of a representative experiment of three independent transfection experiments are presented as the mean ± SEM of four or five samples. **p < 0.01. The transfection efficiencies of each reporter construct shown were normalized to Renilla luciferase activity, an internal transfection standard